1. Field of the Invention
The present invention relates generally to test probe apparatus and more particularly, to adjustable multi-probe test probe head assemblies for electro-mechanical interface contact with terminals of miniature electronic devices.
2. Description of the Prior Art
The practice of testing electrical characteristics of miniature electronic devices, e.g., semiconductor components, integrated circuit components, micro and printed circuits, etc., is important to the electronic device manufacturer. Testing prior to and after final assembly of the devices is generally conducted to determine performance capabilities and defects. For example, it is desirable to test semiconductor devices while they are in wafer or slice form so as to eliminate unsatisfactory components early in the manufacturing process. For quality assurance, the manufacturer tests the devices after final assembly and prior to shipment. Manufacturers of equipment in which the devices become a part, commonly test the devices prior to installation of the devices in the equipment. In view of the number of tests conducted and the volume demand for miniature electronic devices, there is a continuous need to provide equipment capable of performing these tests accurately and rapidly.
With heretofore adjustable probe heads, the positional adjustment of the probe points is difficult. They generally require use of a trial-and-error process of adjustment of the probe points for each set-up in each of three orthogonal planes. Changing the probe point position in any one of the three planes generally results in a change of the probe point position in one or both of the other planes.
Examples of probe head assemblies of the prior art are disclosed in U.S. Pat. No. 3,832,632 and U.S. Pat. No. 3,891,924, issued to Frank J. Ardezzone, et al; U.S. Pat. No. 3,702,439 granted to McGahey et al; U.S. Pat. No. 3,405,361 granted to L. E. Kattner et al; and U.S. Pat. No. 3,445,770 granted to R. C. Harman.